diff --git a/autoload.php b/autoload.php
index c295b2ea75..e61c472fb1 100644
--- a/autoload.php
+++ b/autoload.php
@@ -210,7 +210,7 @@ public static function determineLoadedClass($classesBeforeLoad, $classesAfterLoa
             // That way, at the end, only the "main" class just included will remain.
             $newClasses = array_reduce(
                 $newClasses,
-                function ($remaining, $current) {
+                static function ($remaining, $current) {
                     return array_diff($remaining, class_parents($current));
                 },
                 $newClasses
diff --git a/src/Reports/Summary.php b/src/Reports/Summary.php
index 165ad64b0c..1b048e6796 100644
--- a/src/Reports/Summary.php
+++ b/src/Reports/Summary.php
@@ -98,7 +98,7 @@ public function generate(
 
         uksort(
             $reportFiles,
-            function ($keyA, $keyB) {
+            static function ($keyA, $keyB) {
                 $pathPartsA = explode(DIRECTORY_SEPARATOR, $keyA);
                 $pathPartsB = explode(DIRECTORY_SEPARATOR, $keyB);
 
diff --git a/src/Sniffs/AbstractPatternSniff.php b/src/Sniffs/AbstractPatternSniff.php
index d9528dccf8..c6d0e34806 100644
--- a/src/Sniffs/AbstractPatternSniff.php
+++ b/src/Sniffs/AbstractPatternSniff.php
@@ -744,17 +744,17 @@ protected function registerSupplementary()
     }//end registerSupplementary()
 
 
-     /**
-      * Processes any tokens registered with registerSupplementary().
-      *
-      * @param \PHP_CodeSniffer\Files\File $phpcsFile The PHP_CodeSniffer file where to
-      *                                               process the skip.
-      * @param int                         $stackPtr  The position in the tokens stack to
-      *                                               process.
-      *
-      * @return void
-      * @see    registerSupplementary()
-      */
+    /**
+     * Processes any tokens registered with registerSupplementary().
+     *
+     * @param \PHP_CodeSniffer\Files\File $phpcsFile The PHP_CodeSniffer file where to
+     *                                               process the skip.
+     * @param int                         $stackPtr  The position in the tokens stack to
+     *                                               process.
+     *
+     * @return void
+     * @see    registerSupplementary()
+     */
     protected function processSupplementary(File $phpcsFile, $stackPtr)
     {
 
diff --git a/src/Standards/PEAR/Sniffs/Commenting/FunctionCommentSniff.php b/src/Standards/PEAR/Sniffs/Commenting/FunctionCommentSniff.php
index d6fe2e8253..34b43e5d17 100644
--- a/src/Standards/PEAR/Sniffs/Commenting/FunctionCommentSniff.php
+++ b/src/Standards/PEAR/Sniffs/Commenting/FunctionCommentSniff.php
@@ -195,7 +195,7 @@ protected function processReturn(File $phpcsFile, $stackPtr, $commentStart)
 
         // Skip constructor and destructor.
         $methodName      = $phpcsFile->getDeclarationName($stackPtr);
-        $isSpecialMethod = in_array($methodName,  $this->specialMethods, true);
+        $isSpecialMethod = in_array($methodName, $this->specialMethods, true);
 
         $return = null;
         foreach ($tokens[$commentStart]['comment_tags'] as $tag) {
diff --git a/src/Standards/Squiz/Sniffs/Commenting/FunctionCommentSniff.php b/src/Standards/Squiz/Sniffs/Commenting/FunctionCommentSniff.php
index c7003faaf2..254c4143b1 100644
--- a/src/Standards/Squiz/Sniffs/Commenting/FunctionCommentSniff.php
+++ b/src/Standards/Squiz/Sniffs/Commenting/FunctionCommentSniff.php
@@ -67,7 +67,7 @@ protected function processReturn(File $phpcsFile, $stackPtr, $commentStart)
 
         // Skip constructor and destructor.
         $methodName      = $phpcsFile->getDeclarationName($stackPtr);
-        $isSpecialMethod = in_array($methodName,  $this->specialMethods, true);
+        $isSpecialMethod = in_array($methodName, $this->specialMethods, true);
 
         if ($return !== null) {
             $content = $tokens[($return + 2)]['content'];
@@ -781,7 +781,7 @@ protected function checkInheritdoc(File $phpcsFile, $stackPtr, $commentStart)
             T_DOC_COMMENT_STAR,
         ];
         for ($i = $commentStart; $i <= $tokens[$commentStart]['comment_closer']; $i++) {
-            if (in_array($tokens[$i]['code'], $allowedTokens) === false) {
+            if (in_array($tokens[$i]['code'], $allowedTokens, true) === false) {
                 $trimmedContent = strtolower(trim($tokens[$i]['content']));
 
                 if ($trimmedContent === '{@inheritdoc}') {
diff --git a/src/Standards/Squiz/Sniffs/Commenting/VariableCommentSniff.php b/src/Standards/Squiz/Sniffs/Commenting/VariableCommentSniff.php
index 055c41604d..2f8d0737f5 100644
--- a/src/Standards/Squiz/Sniffs/Commenting/VariableCommentSniff.php
+++ b/src/Standards/Squiz/Sniffs/Commenting/VariableCommentSniff.php
@@ -127,7 +127,7 @@ public function processMemberVar(File $phpcsFile, $stackPtr)
             return;
         }
 
-         // Support both a var type and a description.
+        // Support both a var type and a description.
         preg_match('`^((?:\|?(?:array\([^\)]*\)|[\\\\a-z0-9\[\]]+))*)( .*)?`i', $tokens[($foundVar + 2)]['content'], $varParts);
         if (isset($varParts[1]) === false) {
             return;
diff --git a/src/Standards/Squiz/Sniffs/PHP/NonExecutableCodeSniff.php b/src/Standards/Squiz/Sniffs/PHP/NonExecutableCodeSniff.php
index f1b9044f10..eac7c20bef 100644
--- a/src/Standards/Squiz/Sniffs/PHP/NonExecutableCodeSniff.php
+++ b/src/Standards/Squiz/Sniffs/PHP/NonExecutableCodeSniff.php
@@ -68,7 +68,7 @@ public function process(File $phpcsFile, $stackPtr)
         $prev = $phpcsFile->findPrevious(Tokens::$emptyTokens, ($stackPtr - 1), null, true);
 
         // Allow for PHP 8.4+ fully qualified use of exit/die.
-        if ($tokens[$stackPtr]['code'] === \T_EXIT && $tokens[$prev]['code'] === \T_NS_SEPARATOR) {
+        if ($tokens[$stackPtr]['code'] === T_EXIT && $tokens[$prev]['code'] === T_NS_SEPARATOR) {
             $prev = $phpcsFile->findPrevious(Tokens::$emptyTokens, ($prev - 1), null, true);
         }
 
diff --git a/src/Standards/Squiz/Sniffs/WhiteSpace/FunctionOpeningBraceSpaceSniff.php b/src/Standards/Squiz/Sniffs/WhiteSpace/FunctionOpeningBraceSpaceSniff.php
index 3eff4e0fff..159aece6b3 100644
--- a/src/Standards/Squiz/Sniffs/WhiteSpace/FunctionOpeningBraceSpaceSniff.php
+++ b/src/Standards/Squiz/Sniffs/WhiteSpace/FunctionOpeningBraceSpaceSniff.php
@@ -63,9 +63,9 @@ public function process(File $phpcsFile, $stackPtr)
         $nextContent = $phpcsFile->findNext(T_WHITESPACE, ($openBrace + 1), null, true);
 
         if ($nextContent === $tokens[$stackPtr]['scope_closer']) {
-             // The next bit of content is the closing brace, so this
-             // is an empty function and should have a blank line
-             // between the opening and closing braces.
+            // The next bit of content is the closing brace, so this
+            // is an empty function and should have a blank line
+            // between the opening and closing braces.
             return;
         }
 
diff --git a/src/Util/Cache.php b/src/Util/Cache.php
index 408de96e7d..e0ee9c8b4b 100644
--- a/src/Util/Cache.php
+++ b/src/Util/Cache.php
@@ -105,7 +105,7 @@ public static function load(Ruleset $ruleset, Config $config)
         );
         $filter = new RecursiveCallbackFilterIterator(
             $di,
-            function ($file, $key, $iterator) {
+            static function ($file, $key, $iterator) {
                 // Skip non-php files.
                 $filename = $file->getFilename();
                 if ($file->isFile() === true && substr($filename, -4) !== '.php') {
diff --git a/src/Util/MessageCollector.php b/src/Util/MessageCollector.php
index 6db9414c18..bd9991c49a 100644
--- a/src/Util/MessageCollector.php
+++ b/src/Util/MessageCollector.php
@@ -298,7 +298,7 @@ private function arrayColumn(array $input, $columnKey)
         }
 
         // PHP 5.4.
-        $callback = function ($row) use ($columnKey) {
+        $callback = static function ($row) use ($columnKey) {
             return $row[$columnKey];
         };
 
diff --git a/tests/Core/Tokenizers/PHP/DNFTypesTest.php b/tests/Core/Tokenizers/PHP/DNFTypesTest.php
index 312df1b378..9e17d4d134 100644
--- a/tests/Core/Tokenizers/PHP/DNFTypesTest.php
+++ b/tests/Core/Tokenizers/PHP/DNFTypesTest.php
@@ -451,16 +451,16 @@ public static function dataDNFTypeParentheses()
                 'testMarker' => '/* testDNFTypeWithPHP84FinalKeywordAndStatic */',
             ],
             'OO property type: asymmetric visibility, private(set)'       => [
-                'testMarker'  => '/* testDNFTypePropertyWithPrivateSet */',
+                'testMarker' => '/* testDNFTypePropertyWithPrivateSet */',
             ],
             'OO property type: asymmetric vis, public private(set)'       => [
-                'testMarker'  => '/* testDNFTypePropertyWithPublicPrivateSet */',
+                'testMarker' => '/* testDNFTypePropertyWithPublicPrivateSet */',
             ],
             'OO property type: asymmetric visibility, protected(set)'     => [
-                'testMarker'  => '/* testDNFTypePropertyWithProtectedSet */',
+                'testMarker' => '/* testDNFTypePropertyWithProtectedSet */',
             ],
             'OO property type: asymmetric vis, public protected(set)'     => [
-                'testMarker'  => '/* testDNFTypePropertyWithPublicProtectedSet */',
+                'testMarker' => '/* testDNFTypePropertyWithPublicProtectedSet */',
             ],
             'OO property type: with only abstract keyword'                => [
                 'testMarker' => '/* testDNFTypeWithPHP84AbstractKeyword */',